Magnetoplasmonics Lab

Ultrafast switching of tunable infrared plasmons in indium tin oxide nanorod arrays with large absolute amplitude

Ultrafast switching of tunable infrared plasmons in indium tin oxide nanorod arrays with large absolute amplitude

12345

 

All-optical control of plasmons can enable optical switches with high speeds, small footprints and high on/off ratios. Here Guo et al., demonstrate ultrafast plasmon modulation in the near-infrared (NIR) to mid-infrared (MIR) range by intraband pumping of indium tin oxide nanorod arrays (ITO-NRAs). They observe redshifts of localized surface plasmon resonances arising from a change of the plasma frequency of ITO, which is governed by the conduction band non-parabolicity. They generalize the plasma frequency for non-parabolic bands, quantitatively model the fluence-dependent plasma frequency shifts, and show that different from noble metals, the lower electron density in ITO enables a remarkable change of electron distributions, yielding a significant plasma frequency modulation and concomitant large transient bleaches and induced absorptions, which can be tuned spectrally by tailoring the ITO-NRA geometry. The low electron heat capacity explains the sub-picosecond kinetics that is much faster than noble metals. Their work demonstrates a new scheme to control infrared plasmons for optical switching, telecommunications and sensing.

 

The news was sent to the administrator by Nasrin Asgari.

PUBLISHED ONLINE date of  the paper: 22 FEBRUARY 2016

Source: DOI: 10.1038/NPHOTON.2016.14

Leave a Reply